Michael Cavallari's death ruled an accident, autopsy report says he died of hypothermia

The death of Jay Cutler's brother-in-law was ruled accidental after his car crashed while passing through a mountainous, rural part of southern Utah, the Associated Pressreports. The autopsy report says Michael died of hypothermia due to the below-freezing temperatures.

Grand County Sheriff Steven White tells AP that officials are still waiting on the toxicology report to determine if any drugs were in Michael's system at the time of his death.

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Michael Cavallari's death ruled an accident, autopsy report says he died of hypothermia

NEW YORK, NY - SEPTEMBER 17: Kristin Cavallari attends the Kristin Cavallari By Chinese Laundry presentation at Row NYC on September 17, 2015 in New York City. (Photo by Grant Lamos IV/Getty Images)

NEW YORK, NY - SEPTEMBER 16: Kristin Cavallari attends The Blonds show during Spring 2016 MADE Fashion Week at Milk Studios on September 16, 2015 in New York City. (Photo by Andrew Toth/FilmMagic)

CENTURY CITY, CA - MAY 09: Kristin Cavallari attends the JDRF LA 2015 Imagine Gala at the Hyatt Regency Century Plaza on May 9, 2015 in Century City, California. (Photo by Todd Williamson/Getty Images for JDRF)

CENTURY CITY, CA - MAY 09: Kristin Cavallari and Jay Cutler attend the JDRF LA 2015 Imagine Gala at the Hyatt Regency Century Plaza on May 9, 2015 in Century City, California. (Photo by Todd Williamson/Getty Images for JDRF)

NEW YORK, NY - FEBRUARY 12: Kristin Cavallari attends the Go Red For Women fall 2015 fashion show on February 12, 2015 in New York City. (Photo by Taylor Hill/FilmMagic)

NEW YORK, NY - FEBRUARY 13: Kristin Cavallari attends the August Getty fashion show during Mercedes-Benz Fashion Week Fall 2015 at The Salon at Lincoln Center on February 13, 2015 in New York City. (Photo by Stephen Lovekin/Getty Images for Mercedes-Benz Fashion Week)

WEST HOLLYWOOD, CA - OCTOBER 23: Reality TV Personality Kristin Cavallari attends the Life & Style Weekly's 10th anniversary party at SkyBar at the Mondrian Los Angeles on October 23, 2014 in West Hollywood, California. (Photo by Paul Archuleta/FilmMagic)

LOS ANGELES, CA - OCTOBER 23: Kristin Cavallari is seen on October 23, 2014 in Los Angeles, California. (Photo by Bauer-Griffin/GC Images)

NEW YORK, NY - SEPTEMBER 11: Kristin Cavallari attends STYLE360 Hosts Kristin Cavallari By Chinese Laundry Preview Party At Row NYC at Row NYC on September 11, 2014 in New York City. (Photo by Thomas Concordia/WireImage for STYLE360)

BEVERLY HILLS, CA - JULY 27: TV personality Kristin Cavallari attends the International Fashion Film Awards held at the Saban Theatre on July 27, 2014 in Beverly Hills, California. (Photo by Tommaso Boddi/WireImage)

LOS ANGELES, CA - APRIL 09: Kristin Cavallari is seen on April 09, 2014 in Los Angeles, California. (Photo by Bauer-Griffin/GC Images)

LOS ANGELES, CA - APRIL 09: Kristin Cavallari is seen at LAX on April 09, 2014 in Los Angeles, California. (Photo by GVK/Bauer-Griffin/GC Images)

PASADENA, CA - APRIL 08: Kristin Cavallari arrives at the NBCUniversal's 2014 Summer Press Day held at Langham Hotel on April 8, 2014 in Pasadena, California. (Photo by Michael Tran/FilmMagic)

Michael's body was found nearly two weeks after his abandoned car was located by a rancher about 200 miles south of Salt Lake City, Utah. Police say the engine was still running and the air bag was deployed when they the vehicle was located. Michael's body was found on Dec. 10 at the bottom of a steep hill.

Four days prior to when his car was found, Michael was arrested in California on allegations that he threatened a woman while armed with a shotgun.

Just over a month after the death of her brother, Kristin was involved in a car accident herself that sent her to the hospital and left her with minor injuries. "I'll be honest, getting in this car accident and everything else that's been going on in my life the last few months. I have such an appreciation for life," The Hills star told ET's Jennifer Peros earlier this month. "I'm just grateful for everyone and everything in my life."